Reversing switch for a power tool with separate selectively movable contact carriers

ABSTRACT

A common contact is arranged for connection to one of the two lines of an electric power source; a second common contact is arranged for connection to the field windings of the motor. A pair of contact strips is arranged for respective connection to the sides of a motor armature which is wound for rotation in both directions. A pair of movable contacts is mounted by a respective pair of contact carriers for slidable engagement with the contact strips. A reversing arm actuates a shuttle for connecting a selected one of the contact carriers for movement by the trigger from an &#39;&#39;&#39;&#39;off&#39;&#39;&#39;&#39; position wherein the associated movable contact is in engagement with the first common contact and out of engagement with the second common contact to an &#39;&#39;&#39;&#39;on&#39;&#39;&#39;&#39; position wherein said movable contact is in engagement with the second common contact and out of engagement with the first common contact.

United States Patent [1 1 Kaman et al.

.[ 1 Aug. 28, 1973 [75] Inventors: Frank A. Kaman, Prospect Heights;

Conrad D. Robertson, Northbrook;

Ignacy Supel, Chicago, all of 111.

[73] Assignee: Skie Corporation, Chicago, 111.

[22] Filed: July 27, 1972 [2]] Appl. No.: 275,701

[52] 11.8. CI 200/157, 200/1 V, 318/292 [51] Int. Cl. H0111 13/08 [58]Field of Search 200/157, 1 V, 61.85,

200/16 R, 5 R; 318/292; 310/68 A, 50; 173/170 [56] References CitedUNITED STATES PATENTS 3,594,523 7/1971 Frenzel 200/157 3,603,757 9/1971Sahrbacker 200/157 3,632,936 1/1972 Piber 200/157 3,689,715 9/1972 Glenn200/16 R Primary ExaminerRobert K. Schaefer Assistant Examiner-Robert A.Vanderhye Attorney-McDoughall, Hersh & Scott [5 7] ABSTRACT A commoncontact is arranged for connection to one of the two lines of anelectric power source; a second common contact is arranged forconnection to the field windings of the motor. A pair of contact stripsis arranged for respective connection to the sides of a motor armaturewhich is wound for rotation in both directions. A pair of movablecontacts is mounted by a respective pair of contact carriers forslidable engagement with the contact strips. A reversing arm actuates ashuttle for connecting a selected one of the contact carriers formovement by the trigger from an off position wherein the associatedmovable contact is in engagement with the first common contact and outof engagement with the second common contact to an on position whereinsaid movable contact is in engagement with the second common contact andout of engagement with the first common contact.

10 Claims, 8 Drawing Figures PATENTEDAucze rm 755 640 SHEETIBFZ FIGJ I14 it I? 4 FJGLZ 1 REVERSING SWITCH FOR A POWER TOOL WITH SEPARATESELECTIVELY MOVABLE CONTACT CARRIERS BACKGROUND OF THE INVENTION 1.Field of the Invention The present invention relates to a switch unit ordevice adapted for mounting in the housing of aportable tool, such as anelectric drill, for control of the tool motor in response to movement ofa trigger which forms a part of the switch unit. In particular, thepresent invention relates to such a switch unit having a contactarrangement for reversing the direction of current flow through thearmature windings thereby to energize the associated tool in bothforward and reverse directions.

2. The Prior Art Representative prior art US. Pat. Nos. are Frenzel3,260,827, Matthews 3,467,801, Braun 3,637,967 and Johnson 3,649,780.These patents show trigger operated switch devices for mounting inportable tools, such as electric drills, to energize the tool motor inboth forward and reverse directions. The devices shown in these patentsmay also include a speed control circuit of the type disclosed andclaimed in Gawron US. Pat. No. 3,209,228 whereby the speed of the toolmotor may be varied in both directions of rotation thereof in responseto the amount of trigger depression.

The prior art represented by these patents suffers from the disadvantagethat the reversing contact construction is somewhat complex with theattendant disadvantage of high cost. These reversing switches which alsoinclude the speed control circuit have the reversing contacts in theform of a separate switch attached to the main body or housing whichincludes the speed control circuit this results in a rather large devicemaking assembly in a small portable tool housing difficult in someinstances. The prior art reversing switch units which include speedcontrol are also disadvantageous in that they necessarily include aduplication of contacts and are in essence two separate switches, i.e.,a speed control switch and a reversing switch, connected together in onemodule.

SUMMARY AND OBJECTS OF THE INVENTION The present invention relates to areversing switch for a portable tool or the like, which switch embodiesa unique arrangement of reversible contacts, which contacts permitintegrating of the reversing switch with a speed control circuit.

A primary object of the present invention is the provision of a new andimproved reversing switch which is simple to construct and which ishighly reliable in operation.

Another object of the present invention is the provision of a reversingswitch which may be readily integrated with a speed control circuit foran electric motor of a power tool.

Still another object of the present invention is the provision of thereversing switch of the type described which includes first and secondcommon contacts, a pair of movable contacts and respective carrierstherefor, whereby a selected one of the contact carriers may beconnected with the trigger for movement of the associated movablecontact from an off" position wherein said movable contact is inengagement with the first common contact and out of engagement with thesecond contact to an on position wherein said movable contact is inengagement with said second common contact and out of engagement withsaid first common contact.

These and other objects and advantages of the present invention willbecome apparent from the following specification disclosing a preferredembodiment shown in the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. I is a side elevational view of theswitch unit or device embodying the present invention;

FIG. 2 is a top plan view of the switch device;

FIG. 3 is an enlarged section taken along the line 33 of FIG. 2;

FIG. 4 is a front elevation of the switch device;

FIG. 5 is a fragmentary exploded isometric, largely diagrammatic inform', primarily showing the arrangement of the contacts and thecarriers for the movable contacts;

FIG. 6 is a circuit diagram, largely schematic in form, showing thereversing switch in the off" position;

FIG. 7 is a circuit diagram, largely schematic in form, showing thereversing switch energizing the tool motor in one direction of rotationthereof through an associated speed control circuit; and

FIG. 8 is a circuit diagram, largely schematic in form, showing thereversing switch energizing the tool motor in its other direction ofrotation and with the speed control circuit being bypassed.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring particularly to FIGS. 1and 2, the present invention is embodied in a switch unit or device,generally designated 10, which device includes a housing 1 1, generallyin the fonn of a parallelepiped, mounting a trigger 12, a reversing arm14 and a locking plunger 15. It will be understood that the switch unit10 is adapted for mounting withinthe housing of a portable electrictool, such as an electric drill, which tool housing includes suitableapertures for exposing the trigger 12, the reversing arm 14 and theplunger 15 for manipulation by the operator of the tool. It will also beunderstood that the associated portable tool includes a motor having anarmature wound for rotation in both directions, which directions will bereferred to as forward" and reverse." The trigger l2 and reversing arm14 are preferably juxtaposed for convenient operation as disclosed andclaimed in Frenzel US. Pat. No. 3,260,827, assigned to the assignee ofthe present application.

The housing 11 includes a top wall 17, side walls 18, a front wall 19and a rear wall 20, the housing being open at the bottom thereof forreception of a housing subassembly, generally designated 22. The frontwall 19 includes an aperture 23 for receiving the trigger 12. It will beunderstood that the trigger is suitably mounted, as by guideways or thelike, for reciprocal movement relative to the housing. The trigger 12may include adjustment mechanism as disclosed and claimed in FrenzelReissue US. Pat. No. Re. 26,781, assigned to the assignee of the presentapplication,

which mechanism is operated by an adjustment button 24 to vary thestroke of the trigger. Since such adjustment mechanism forms no part ofthe present invention, no further reference herein will be made thereto.

The opening 23 in the front housing wall 19 also receives the reversingarm 14. This arm includes a blind bore 26 on its underside andintermediate its ends for receiving a pin 27 formed on a member 28, thelatter being a part of the housing 11. It will be apparent the reversingarm 14 is mounted for pivoting or swinging movement in a horizontalplane about an axis defined by the pin 27. The reversing arm 14preferably includes a pin 29 to prevent movement of the reversing armunless the trigger is in its extended position, all as fully describedin the aforesaid Frenzel U.S. Pat. No. 3,260,827.

The trigger 12 includes a cavity 30 in the underside thereof forreceiving a pair of contact carriers 31, 32. The trigger 12 alsoincludes a rearwardly extending tongue portion 34 having a transverselyextending opening 35, the walls of which are stepped to form slideways36. A shuttle 37 is slidably mounted in the opening 35, which shuttlehas shoulders 38 in sliding engagement with the slideways 36. Theshuttle 37 'includes an upwardly extending pin 40 received within acutout 41 in the inner end of the reversing arm 14. It should beapparent that swinging movement of the reversing arm will result insliding movement of the shuttle from one end of the opening 35 to theother end thereof.

The contact carrier 31 includes a pocket 43 opening at the top of thecontact carrier and at one side thereof. Similarly, the contact carrier32, which is of identical but opposite hand construction with thecarrier 31, includes a pocket 44. These pockets are adapted foralternately receiving the depending portion 45 of the shuttle 37 and forpermitting sliding movement of the shuttle fron one pocket to the otherwhen the contact carriers are in side-by-side alignment as shown in FIG.5. When the shuttle is received in the pocket 43, the contact carrier 31is connected with the trigger 12 for movement in unison with the latter,the contact carrier 32 at such time being disconnected from the trigger.

When the shuttle 37 is received within the pocket 44, the contactcarrier 32 is connected with the trigger l2 and the contact carrier 31disconnected from the trigger.

A coil spring 47 has one end thereof received within an opening 48formed in the contact carrier 31, the other end of this spring being inabutting engagement with the inside surface of the rear housing wall 20.Another spring 49 abuts the rear housing wall 29 and is also receivedwithin an opening (not shown) in the contact carrier 32. The springs 47,49 urge the contact carriers to the right as seen in FIG. 3.

The contact carrier 31 includes a longitudinally extending slot 51 forreception of a bridging contact 52, which bridging contact includes anupstanding ear 52a and contact faces 52b, 520. The carrier 31 includes apocket for receiving the ear 52a. A coil spring 53 has its upper endreceived within a blind bore 54 formed in the contact carrier 31, thelower end of this spring bearing downwardly against the bridging contact52 for urging the same into engagement with fixed contacts to bedescribed hereinbelow. Similarly, the contact carrier 32 includes a slot56 for reception of a bridging contact 57, the latter being urgeddownwardly by a coil spring 58. The bridging contact 57, which isidentical with the bridging contact 52, includes an upstanding ear 57aand contact faces 57b, 57c.

The subassembly 22 is generally in the form of a parallelepiped havingits top defined by a dielectric contact mounting board 60. The board 60mounts a common contact 61 including contact formations 61a, 61b as wellas a depending terminal 61c. The contact board 60 also mounts a pair ofparallel spaced contact strips 62, 63 having respective dependingterminals 62a, 63a. A common contact bar 65 is mounted on the board 60in perpendicular spaced relationship with the strips 62, 63. Finally,the board 60 mounts another common contact bar 66 having a dependingterminal portion 660. At this time it should be mentioned that thesubassembly 22 includes a contact 68 having a first terminal 68a and asecond terminal 68b. This contact serves only as a convenient means formaking the connection between the field windings of the motor and thesource of alternating current; the contact 68 serves no function as faras the switching operation is concerned. It will also be noted that thesix contact terminals 610, 62a, 63a, 66a, 68a and 68b are in the form ofpush-in terminals and are received in respective cavities opening at thebase of the subassembly 22 thereby to facilitate connection with thevarious lead wires.

The subassembly 22 includes a compartment (not shown) for reception of avertically disposed ceramic circuit board, generally designated 70 (FIG.4). It will be understood that this circuit board, which is of the typedisclosed and claimed in Robertson U.S. Pat. No. 3,543,120, mounts thevarious electronic components constituting a speed control circuit ofthe type disclosed and claimed in Gawron U.S. Pat. No. 3,209,228, eachof these patents being assigned to the assignee of the presentinvention. The contact board 60 includes an elongated slot 71 forreceiving the upper portion of the circuit board 70, which upper portionmounts resistance strips forming part of the variable resistor of thespeed control circuit, as fully explained in the aforesaid Robertsonpatent.

Referring now to FIG. 6, the circuit board 70 includes a pair ofcolinear resistance strips 72, 73 adapted to be slidably engaged by thecontact slider 74. It will be understood that the trigger 12 includes acavity for receiving the slider 74 thereby to impart sliding movement tothe latter along the resistance strips 72, 73 in response to reciprocalmovement of the trigger. The circuit board 70 further includes acontrollable semiconductor 76, which may be a silicon controlledrectifier, for example. The board 70 mounts a capacitor 77 and asuitable triggering device 78. The circuit board 70 includes a pair ofcontact strips 80 and 81 which are bent over horizontally and connectedto the respective contact bars 65, 66, as by soldering. Reference shouldbe had to the aforementioned Robertson and Gawron patents for a detaileddescription of the speed control circuit.

As seen in FIG. 6, the contact strip terminals 620 and 63a arerespectively connected to the sides of an armature 82, which armature iswound for rotation in both forward and reverse directions. The fieldwindings 83 of the motor are connected to the terminal 660 of thecontact bar 66 and to the terminal 68a of the contact 68. The two lines84, 85 from the source of alternating current are respectively connectedto the terminals 61c and 68b.

The operation of the reversing switch according to the present inventionis as follows:

The switch unit is shown in the off position in FIG. 3. In such positionthe contact face 52b is engaged with the contact strip 62 and the ear52a is in engagement with the contact formations 61a. It is noted thatthe contact face 520 is out of engagement with the contacts on the board60. Similarly, in the off position, the contact face 57b is inengagement with the contact strip 63, the ear 57a is in engagement withthe contact formation 61b, and the contact face 57c is out of engagementwith the contacts on the board 60.

Assume it is desired to energize the motor in the forward" direction.The reversing arm 14 is swung to the position shown in FIG. 3 therebypositioning the shuttle 37 in the pocket 43 of the contact carrier 31.When the trigger is depressed, corresponding movement will be impartedto the contact carrier 31 as such carrier is now connected to thetrigger for movement therewith by means of the shuttle; the'contactcarrier 32 will not be moved at this time as the same is disengaged fromthe trigger.

Initial movement of the contact carrier 31 will cause the ear 52a to beseparated from the contact formation 61a followed by snapping of thecontact face 52c into engagement with the contact bar 65 as the bridgingcontact 52 pivots about the point of engagement between the contact face52b and the strip 62. At this time it should be mentioned that thebridging contacts 52, 57 are preferably mounted and independentlysnapped into engagement with the bar 65 and separated from the bar 65 inthe manner disclosed and claimed in Frenzel US. Pat. No. 3,594,523,assigned to the assignee of the present invention.

The arrangement of the contacts as just described is schematicallyrepresented in FIG. 7. The circuit through the motor is as follows:terminal 61c, contact formation 61b, contact ear 57a, contact strip 63,terminal 63a, armature 82, terminal 62a, contact strip 62, contact faces52b, 52c, bar 65, contact strip 80, the speed control circuit on theceramic circuit board 70, contact strip 81, bar 66, terminal 66a, fieldwindings 83, and contact 68.

Accordingly, the motor is energized in the forward direction and at aspeed proportional to the amount the trigger is depressed. As thetrigger is continued to be squeezed, the contact faces 52b, 52c slidealong the respective contacts 62, 65. Such movement of the triggercauses corresponding movement of the slider 74 along the resistancestrips 72, 73 progressively increasing the speed of the motor as morefully explained in the aforementioned Robertson and Gawron patents.

Continued squeezing of the trigger will cause the contact face 52c toseparate from the contact bar 65 and come into engagement with thecontact bar 66. This movement of the trigger will result in energizationof the motor in the forward direction at full speed independently of thespeed control circuit as follows: terminal 61c, contact formation 61b,contact ear 57a, contact face 57b, contact strip 63, terminal 63a,armature 82, terminal 620, contact strip 62, contact faces 52b, 52 0,bar 66, terminal 66a, field windings 83, and contact 68.

As the trigger is released, the motor will again be energized in theforward direction through the speed control circuit from the high speedmode of operation and to low speed as the trigger is progressivelyextended. When the trigger is fully extended, the bridging contact 52will be rocked to the position shown in FIG. 3 thereby againestablishing the 0H position as seen in FIG. 6.

Now assume it is desired to energize the motor in the other or reversedirection. The reversing arm 14 is swung to its other position therebysliding the shuttle from the pocket 43 to the pocket 44. This willresult in disconnecting the contact carrier 31 from the trigger l2 andconnecting the contact carrier 32 to the trigger for movement therewith.Now, when the trigger is depressed, the contact face 57c will be snappedinto engagement with the contact bar 66 after separation of the contactear 57a from the contact formation 61b.

The circuit through the armature is as follows: terminal 61c, contactformation 61a, contact ear 52a, contact face 52b, contact strip 62,terminal 62a, armature 82,

terminal 63a, contact bar 65. The circuit path from the contact bar 65to the other terminal in the reverse direction is the same as describedabove in connection iwth the forward direction of rotation.

FIG. 8 illustrates the arrangement of contacts when the reversing arm 14is in the reverse position and when the trigger is fully depressed. Itwill be apparent that in such position of the reversing arm and trigger,the motor will be energized in the reverse direction of rotation at fullspeed independently of the speed control circuit.

It will be appreciated that the present invention provides a new andimproved arrangement of contacts for reversing the direction of rotationof an electric motor. The present invention has particular applicabilityin a reversing switch of the trigger actuated type adapted for mountingwithin the housing of a portable electric tool. The arrangement ofcontacts according to the present invention may be readily integratedwith a contact arrangement forming part of a speed control circuit ofthe type which includes a variable resistor for varying the speed of themotor in response to the amount of trigger movement. However, it will beunderstood the present invention is not to be limited for use inassociation with a speed control circuit.

We claim:

1. A reversing switch for an electric motor comprising:

a. first common contact means arranged for connec tion to one of the twolines of an electric power source;

b. second common contact means arranged for connection to the fieldwindings of said motor;

c. a pair of movable contacts and a pair of respective carrierstherefor; I

-d. means respectively connecting said movable contacts to a pair ofterminals arranged for connection to the respective sides of a motorarmature of the type wound for rotation in both directions;

. first actuator means for moving a selected one of said contactcarriers from an off position wherein the associated movable contact isin engagement with said first common contact means and out of engagementwith said second common contact means to an "on" position wherein saidmovable contact is in engagement with said second common contact meansand out of engagement with said first common contact means; and

. second actuator means for alternately connecting one or the other ofsaid contact carriers for movement byjsaid first actuator means.

2. The reversing switch according to claim 1 wherein said meansconnecting said movable contacts to said armature comprise a pair ofcontact strips respectively 'slidably engaged by said movable contacts.

3. The reversing switch according to claim 2 further defined by:

a. means defining a speed control circuit of the type including avariable resistor, which circuit is connected to said second commoncontact means;

b. a contact slider forming part of said variable resistor; and

c. means connecting said contact slider with said first actuator meansfor movement of the former in response to movement of the latter.

4. The reversing switch according to claim 3 further defined by thirdcommon contact means connected with said speed control circuit andarranged for connection within the field windings of said motor, saidfirst actuator means being adapted to move a selected one of saidcontact carriers from said on position to a bypass position wherein theassociated movable contact is in engagement with said third commoncontact means and out of engagement with said first and second commoncontact means.

5. A reversing switch for a portable tool of the type powered by anelectric motor of the reversible type comprising:

a. a switch housing adapted for mounting within the housing of a powertool;

b. a trigger and a reversing member mounted by said housing forindependent movement relative thereto;

c. first common contact means mounted in said housing and connected witha first terminal arranged for connection to one of the two lines of anelectric power source;

d. second common contact means mounted in said housing and connectedwith a second terminal arranged for connection to the field windings ofsaid motor;

e. said housing containing a pair of movable contacts and a pair ofrespective carriers therefor;

fv first means in said housing respectively connecting said movablecontacts to third and fourth terminals which third and fourth terminalsare arranged for connection to the respective sides ofa motor armatureof the type wound for rotation in both directions; and

g. second means in said housing movable, in response to movement of saidreversing member back and forth between forward and reverse positions,for connecting a selected one of said contact carriers with said triggerfor movement of the former, in response to movement of the latter, froman of position wherein the associated movable contact is in engagementwith said first common contact means and out of engagement with saidsecond common contact means to an on" position wherein said movablecontact is in engagement with said second common contact means and outof engagement with said first common contact means.

6. The reversing switch according to claim 5 wherein said first meansincludes a pair of contact strips respectively slidably engaged by saidmovable contacts.

7. The reversing switch according to claim 6 further defined by: I

a. means in said housing defining a speed control circuit of the typeincluding a variable resistor, which circuit is connected between saidsecond common contact means and said second terminal;

b. a contact slider forming part of said variable resistor; and

c. third means connecting said contact slider with said trigger formovement of the former in response to movement of the latter.

8. The reversing switch according to claim 7 further defined by, thirdcommon contact means connected between said speed control circuit andsaid second terminal said trigger being adapted to move a selected oneof said contact carriers from said on position to a bypass positionwherein the associated movable contact is in engagement with said thirdcommon contact means and out of engagement with said first and secondcommon contact means.

9. The reversing switch according to claim 5 further defined by:'

a. said first means including a pair of contact strips extending inparallel spaced relation with each other and also being parallel withthe direction of trigger movement, which strips are respectivelyslidably engaged by said movable contacts;

b. a pair of springs respectively engaged with said contact carriers foryieldably holding said-movable contacts in said off position;

c said contact carriers each having a pocket; and

d. said second means including a shuttle engaged with said reversingmember and movably mounted by said trigger, said shuttle beingalternately received in said pockets for establishing the connectionbetween said trigger and the selected one of said contact carriers.

10. The reversing switch according to claim 9 further defined by, meansdefining a speed control circuit of the type including a variableresistor, which circuit is connected between said second common contactmeans and said second terminal;

b. a contact slider forming part of said variable resistor; and c. thirdmeans connecting said contact slider with said trigger for movement ofthe former in response to movement of the latter.

1. A reversing switch for an electric motor comprising: a. first commoncontact means arranged for connection to one of the two lines of anelectric power source; b. second common contact means arranged forconnection to the field windings of said motor; c. a pair of movablecontacts and a pair of respective carriers therefor; d. meansrespectively connecting said movable contacts to a pair of terminalsarranged for connection to the respective sides of a motor armature ofthe type wound for rotation in both directions; e. first actuator meansfor moving a selected one of said contact carriers from an ''''off''''position wherein the associated movable contact is in engagement withsaid first common contact means and out of engagement with said secondcommon contact means to an ''''on'''' position wherein said movablecontact is in engagement with said second common contact means and outof engagement with said first common contact means; and f. secondactuator means for alternately connecting one or the other of saidcontact carriers for movement by said first actuator means.
 2. Thereversing switch according to claim 1 wherein said means connecting saidmovable contacts to said armature comprise a pair of contact stripsrespectively slidably engaged by said movable contacts.
 3. The reversingswitch according to claim 2 further defined by: a. means defining aspeed control circuit of the type including a variable resistor, whichcircuit is connected to said second common contact means; b. a contactslider forming part of said variable resistor; and c. means connectingsaid contact slider with said first actuator means for movement of theformer in response to movement of the latter.
 4. The reversing switchaccording to claim 3 further defined by third common contact meansconnected with said speed control circuit and arranged for connectionwithin the field windings of said motor, said first actuator means beingadapted to move a selected one of said contact carriers from said''''on'''' position to a ''''bypass'''' position wherein the associatedmovable contact is in engagement with said third common contact meansand out of engagement with said first and second common contact means.5. A reversing switch for a portable tool of the type powered by anelectric motor of the reversible type comprising: a. a switch housingadapted for mounting within the housing of a power tool; b. a triggerand a reversing member mounted by said housing for independent movementrelative thereto; c. first common contact means mounted in said housingand connected with a first terminal arranged for connection to one ofthe two lines of an electric power source; d. second common contactmeans mounted in said housing and connected with a second terminalarranged for connection to the field windings of said motor; e. saidhousing containing a pair of movable contacts and a pair of respectivecarriers therefor; f. first means in said housing respectivelyconnecting said mOvable contacts to third and fourth terminals whichthird and fourth terminals are arranged for connection to the respectivesides of a motor armature of the type wound for rotation in bothdirections; and g. second means in said housing movable, in response tomovement of said reversing member back and forth between forward andreverse positions, for connecting a selected one of said contactcarriers with said trigger for movement of the former, in response tomovement of the latter, from an ''''off'''' position wherein theassociated movable contact is in engagement with said first commoncontact means and out of engagement with said second common contactmeans to an ''''on'''' position wherein said movable contact is inengagement with said second common contact means and out of engagementwith said first common contact means.
 6. The reversing switch accordingto claim 5 wherein said first means includes a pair of contact stripsrespectively slidably engaged by said movable contacts.
 7. The reversingswitch according to claim 6 further defined by: a. means in said housingdefining a speed control circuit of the type including a variableresistor, which circuit is connected between said second common contactmeans and said second terminal; b. a contact slider forming part of saidvariable resistor; and c. third means connecting said contact sliderwith said trigger for movement of the former in response to movement ofthe latter.
 8. The reversing switch according to claim 7 further definedby, third common contact means connected between said speed controlcircuit and said second terminal said trigger being adapted to move aselected one of said contact carriers from said ''''on'''' position to a''''bypass'''' position wherein the associated movable contact is inengagement with said third common contact means and out of engagementwith said first and second common contact means.
 9. The reversing switchaccording to claim 5 further defined by: a. said first means including apair of contact strips extending in parallel spaced relation with eachother and also being parallel with the direction of trigger movement,which strips are respectively slidably engaged by said movable contacts;b. a pair of springs respectively engaged with said contact carriers foryieldably holding said movable contacts in said ''''off'''' position; c.said contact carriers each having a pocket; and d. said second meansincluding a shuttle engaged with said reversing member and movablymounted by said trigger, said shuttle being alternately received in saidpockets for establishing the connection between said trigger and theselected one of said contact carriers.
 10. The reversing switchaccording to claim 9 further defined by, means defining a speed controlcircuit of the type including a variable resistor, which circuit isconnected between said second common contact means and said secondterminal; b. a contact slider forming part of said variable resistor;and c. third means connecting said contact slider with said trigger formovement of the former in response to movement of the latter.